Steer-by-wire and the end of crossed arms

A tight turn inside a mall parking ramp works as expected because the steering wheel has always been mechanically linked to the front wheels.

Newer systems change that by removing the physical connection between the steering wheel and the front wheels and replacing it with electronic signals that carry the driver’s input to the steering mechanism.

When the wheel is turned, sensors measure how far and how fast it moves, and a control unit sends instructions to electric motors that turn the front wheels, which means the wheel no longer moves any mechanical part connected to the tires.

Lexus has introduced this technology on the RZ in selected markets with a yoke-style steering control, which is not a full circular wheel and is designed to work with less turning, while Mercedes-Benz has confirmed similar technology for future models using multiple sensors and backup systems so the car can continue to steer even if one part stops working.

A conventional steering system follows a fixed sequence where turning the wheel rotates a shaft, the shaft moves gears in the steering rack, and the rack pushes the wheels left or right, and this relationship stays the same whether the car is moving slowly or at a higher speed.

A steer-by-wire system handles the same input differently because turning the wheel sends an electronic signal instead of a mechanical connection, and the system calculates how much the wheels should turn before sending that command to the motors.

At low speeds, the system allows the wheels to turn more with less movement of the steering control, while at higher speeds, it reduces how much the wheels respond to small movements to keep the car stable.

This difference becomes obvious in tight turns because the driver does not need to cross hands to complete the turn, the way most people do in narrow streets, manifesting our inner April Boy Regino’s “di ko kayang tanggapin” cross-forearm moment.

Earlier versions, such as the one from Infiniti, had a mechanical backup that could reconnect if needed, while newer systems rely on multiple sensors and control units so the car can still steer if one part fails.

The steering wheel still controls the direction of the car, but the input now goes through electronics that read it and tell the wheels how much to turn, so the response can change depending on speed and conditions.

That explains why some new cars feel easier to handle at low speeds and more stable at speed, and why the same turn can feel different the moment you try it in a newer car.